Determination of 30 Per- and Polyfluoroalkyl Substances (PFAS) in Baby Food

Importance of the topic

Per- and polyfluoroalkyl substances (PFAS) are persistent pollutants used in industrial and consumer products that resist degradation and accumulate in the human body. Infants and young children are particularly vulnerable to PFAS exposure, raising concerns over long-term health effects. Recent regulatory limits established by the European Commission and AOAC SMPR 2023.003 highlight the need for robust analytical methods to monitor PFAS in baby food.

Objectives and study overview

This work aimed to develop and validate a streamlined, multiresidue workflow for the quantitation of 30 PFAS in baby food matrices. Key goals included simplified sample preparation, high sensitivity and specificity via LC-MS/MS, and compliance with AOAC SMPR performance requirements for limits of quantitation, accuracy, and precision.

Methodology and data acquisition

Baby food samples containing fruits, vegetables, and grains were homogenized and spiked with native PFAS and isotopically labeled internal standards. Samples (10 g) were extracted with acetonitrile containing 1% acetic acid using QuEChERS salts and homogenizers. The crude extracts underwent Enhanced Matrix Removal (EMR) mixed-mode passthrough cleanup using Agilent Captiva EMR PFAS Food I cartridges. Cleaned eluates were dried, reconstituted in 80:20 methanol/water, and analyzed by LC-MS/MS. Separation was performed on ZORBAX RRHD Eclipse Plus C18 columns with mobile phases of 5 mM ammonium acetate in water (A) and methanol (B). Detection employed an Agilent 6495D triple quadrupole mass spectrometer with Jet Stream iFunnel electrospray source. Calibration was performed with neat standards (10–5000 ng/L) and ISTD normalization, eliminating the need for matrix-matched curves.

Instrumentation

• Agilent 1290 Infinity II LC system (pump, multisampler, thermostat)
• Agilent 6495D LC/TQ mass spectrometer with Jet Stream iFunnel
• Agilent InfinityLab PFC-free HPLC conversion kit
• Agilent QuEChERS EN extraction kit and Captiva EMR PFAS Food I cartridges
• Centrifuge, Geno/Grinder, test tube shaker, positive pressure manifold, CentriVap concentrator

Main results and discussion

EMR cleanup outperformed traditional dispersive SPE cleanup in PFAS recovery and matrix removal. Recoveries of core PFAS (PFOS, PFOA, PFNA, PFHxS) exceeded 70% across validation levels, with repeatability (RSD) below 15%. Matrix interferences were significantly reduced as evidenced by GC/MS full scan and LC/Q-TOF total ion chromatograms. Sample volume recovery after EMR cleanup was >90%, enabling efficient post-concentration. The method achieved validated LOQs of 0.001–0.002 µg/kg for core PFAS and ≤0.01 µg/kg for remaining targets, meeting EU regulatory limits. Calibration curves demonstrated linearity (R² >0.99) over a 500-fold range.

Benefits and practical applications

• Streamlined workflow with two major sample preparation steps vs. three in traditional methods
• Reduced solvent consumption, plastic ware, and hands-on time
• High-throughput capability and improved laboratory productivity
• Reliable quantitation across diverse food matrices using a single ISTD-normalized calibration

Future trends and opportunities for use

Future developments may include extension of EMR cleanup strategies to high-fat and animal-origin foods, integration with high-resolution mass spectrometry for non-target PFAS screening, automation of sample processing, and incorporation of data analytics tools linking PFAS occurrence to exposure risk assessment.

Conclusion

The validated QuEChERS–EMR mixed-mode passthrough cleanup combined with LC-MS/MS detection offers a sensitive, reliable, and efficient method for quantifying 30 PFAS in baby food. It satisfies stringent regulatory requirements while reducing labor and resource demands, supporting quality control and compliance monitoring in the food industry.

References

• European Commission Regulation (EU) 2023/915 on Maximum Levels for Certain Contaminants in Food.
• AOAC Standard Method Performance Requirements (SMPR 2023.003) for PFAS in Food Matrices.
• Genualdi, S. et al. Analytical and Bioanalytical Chemistry 416, 627–633 (2024).